Elevator

ABSTRACT

Elevator, preferably an elevator without machine room. In the elevator, a hoisting machine engages a set of hoisting ropes by means of a traction sheave. The set of hoisting ropes comprises hoisting ropes of substantially circular cross-section. The hoisting ropes support a counterweight and an elevator car moving on their respective tracks. The hoisting rope has a thickness below 8 mm and/or the diameter of the traction sheave is smaller than 320 mm. The contact angle between the hoisting rope or hoisting ropes and the traction sheave is larger than 180°.

The present invention relates to an elevator as defined in the preambleof claim 1.

One of the objectives in elevator development work is to achieve anefficient and economical utilization of building space. In recent years,this development work has produced various elevator solutions withoutmachine room, among other things. Good examples of elevators withoutmachine room are disclosed in specifications EP 0 631 967 (A1) and EP 0631 968. The elevators described in these specifications are fairlyefficient in respect of space utilization as they have made it possibleto eliminate the space required by the elevator machine room in thebuilding without a need to enlarge the elevator shaft. In the elevatorsdisclosed in these specifications, the machine is compact at least inone direction, but in other directions it may have much largerdimensions than a conventional elevator machine.

In these basically good elevator solutions, the space required by thehoisting machine limits the freedom of choice in elevator lay-outsolutions. Some space is needed to provide for the passage of thehoisting ropes. It is difficult to reduce the space required by theelevator car itself on its track and likewise the space required by thecounterweight, at least at a reasonable cost and without impairingelevator performance and operational quality. In a traction sheaveelevator without machine room, mounting the hoisting machine in theelevator shaft is difficult, especially in a solution with machineabove, because the hoisting machine is a sizeable body of considerableweight. Especially in the case of larger loads, speeds and/or hoistingheights, the size and weight of the machine are a problem regardinginstallation, even so much so that the required machine size and weighthave in practice limited the sphere of application of the concept ofelevator without machine room or at least retarded the introduction ofsaid concept in larger elevators. If the size of the machine and thetraction sheave of the elevator is reduced, then a further problem isoften the question of how to ensure a sufficient grip between thehoisting ropes and the traction sheave.

Specification WO 99/43589 discloses an elevator suspended using flatbelts in which relatively small diversion diameters on the tractionsheave and diverting pulleys are achieved. However, the problem withthis solution is the limitations regarding lay-out solutions, thedisposition of components in the elevator shaft and the alignment ofdiverting pulleys. Also, the alignment of polyurethane-coated beltshaving a load-bearing steel component inside is problematic e.g. in asituation where the car is tilted. To avoid undesirable vibrations, anelevator so implemented needs to be rather robustly constructed at leastas regards the machine and/or the structures supporting it. The massiveconstruction of other parts of the elevator needed to maintain alignmentbetween the traction sheave and diverting pulleys also increases theweight and cost of the elevator. In addition, installing and adjustingsuch a system is a difficult task requiring great precision. In thiscase, too, there is the problem of how to ensure sufficient grip betweenthe traction sheave and the hoisting ropes.

On the other hand, to achieve a small rope diversion diameter, ropestructures have been used in which the load-bearing part is made ofartificial fiber. Such a solution is exotic and the ropes thus achievedare lighter than steel wire ropes, but at least in the case of elevatorsdesigned for the commonest hoisting heights, artificial-fiber ropes donot provide any substantial advantage, particularly because they areremarkably expensive as compared with steel wire ropes.

The object of the invention is to achieve at least one of the followingobjectives. On the one hand, it is an aim the invention to develop theelevator without machine room further so as to allow more effectivespace utilization in the building and elevator shaft than before. Thismeans that the elevator must be so constructed that it can be installedin a fairly narrow elevator shaft if necessary. On the other hand, it isan aim of the invention to reduce the size and/or weight of the elevatoror at least those of its machine. A third objective is to achieve anelevator with a thin hoisting rope and/or small traction sheave in whichthe hoisting rope has a good grip/contact on the traction sheave.

The object of the invention should be achieved without impairing thepossibility of varying the basic elevator layout.

The elevator of the invention is characterized by what is presented inthe characterization part of claim 1. Other embodiments of the inventionare characterized by what is presented in the other claims. Someinventive embodiments are also discussed in the description section ofthe present application. The inventive content of the application canalso be defined differently than in the claims presented below. Theinventive content may also consist of several separate inventions,especially if the invention is considered in the light of explicitlyexpressed or implicit subtasks or from the point of view of advantagesor categories of advantages achieved. In this case, some of thedefinitions contained in the claims below may be superfluous from thepoint view of separate inventive concepts. By applying the invention,one or more of the following advantages, among others, can be achieved:

-   -   Due to a small traction sheave, a compact elevator and elevator        machine are achieved    -   By using a small coated traction sheave, the weight of the        machine can easily be reduced even to about half of the weight        of the machines now generally used in elevators without machine        room. For example, in the case of elevators designed for a        nominal load below 1000 kg, this means machines weighing 100-150        kg or even less. Via appropriate motor solutions and choices of        materials, it is even possible to achieve machines weighing less        than 100 kg.    -   A good traction sheave grip and light components allow the        weight of the elevator car to be considerably reduced, and        correspondingly the counterweight can also be made lighter than        in current elevator solutions.    -   A compact machine size and thin, substantially round ropes        permit the elevator machine to be relatively freely placed in        the shaft. Thus, the elevator solution can be implemented in a        fairly wide variety of ways in the case of both elevators with        machine above and elevators with machine below.    -   The elevator machine can be advantageously placed between the        car and a shaft wall.    -   All or at least part of the weight of the elevator car and        counterweight can be carried by the elevator guide rails.    -   In elevators applying the invention, an arrangement of centric        suspension of the elevator car and counterweight can readily be        achieved, thereby reducing the lateral supporting forces applied        to the guide rails.    -   Applying the invention allows effective utilization of the        cross-sectional area of the shaft.    -   The invention reduces the installation time and total        installation costs of the elevator.    -   The elevator is economical to manufacture and install because        many of its components are smaller and lighter than those used        before.    -   The speed governor rope and the hoisting rope are usually        different in respect of their properties and they can be easily        distinguished from each other during installation if the speed        governor rope is thicker than the hoisting ropes; on the other        hand, the speed governor rope and the hoisting ropes may also be        of identical structure, which will reduce ambiguities regarding        these matters in elevator delivery logistics and installation.    -   The light, thin ropes are easy to handle, allowing considerably        faster installation.    -   E.g. in elevators for a nominal load below 1000 kg and a speed        below 2 m/s, the thin and strong steel wire ropes of the        invention have a diameter of the order of only 3-5 mm.    -   With rope, diameters of about 6 mm or 8 mm, fairly large and        fast elevators according to the invention can be achieved.    -   The traction sheave and the rope pulleys are small and light as        compared with those used in conventional elevators.    -   The small traction sheave allows the use of smaller operating        brakes.    -   The small traction sheave reduces the torque requirement, thus        allowing the use of a smaller motor with smaller operating        brakes.    -   Because of the smaller traction sheave, a higher rotational        speed is needed to achieve a given car speed, which means that        the same motor output power can be reached by a smaller motor.    -   Either coated or uncoated ropes can be used.    -   It is possible to implement the traction sheave and the rope        pulleys in such a way that, after the coating on the pulley has        been worn out, the rope will bite firmly on the pulley and thus        a sufficient grip between rope and pulley in this emergency is        maintained.    -   The use of a small traction sheave makes it possible to use a        smaller elevator drive motor, which means a reduction in drive        motor acquisition/manufacturing costs.    -   The invention can be applied in gearless and geared elevator        motor solutions.    -   Although the invention is primarily intended for use in        elevators without machine room, it can also be applied in        elevators with machine room.    -   In the invention a better grip and a better contact between the        hoisting ropes and the traction sheave are achieved by        increasing the contact angle between them.    -   Due to the improved grip, the size and weight of the car and        counterweight can be reduced.    -   The space saving potential of the elevator of the invention is        increased.    -   The weight of elevator car in relation to the weight of the        counterweight can be reduced.    -   The acceleration power required by the elevator is reduced and        the torque required is also reduced.    -   The elevator of the invention can be implemented using a lighter        and smaller machine and/or motor.    -   As a result of using a lighter and smaller elevator system,        energy savings and at the same time cost savings are achieved.    -   It is possible to place the machine in the free space above the        counterweight, thus increasing the space saving potential of the        elevator.    -   By mounting at least the elevator hoisting machine, the traction        sheave and a diverting pulley in a complete unit, which is        fitted as a part of the elevator of the invention, considerable        savings in installation time and costs will be achieved.

The primary area of application of the invention is elevators designedfor transporting people and/or freight. In addition, the invention isprimarily intended for use in elevators whose speed range, in the caseof passenger elevators, is normally about or above 1.0 m/s but may alsobe e.g. only about 0.5 m/s. In the case of freight elevators, too, thespeed is preferably at least about 0.5 m/s, although slower speeds canalso be used with large loads.

In both passenger and freight elevators, many of the advantages achievedthrough the invention are pronouncedly brought out even in elevators foronly 3-4 people, and distinctly already in elevators for 6-8 people(500-630 kg).

The elevator of the invention can be provided with elevator hoistingropes twisted e.g. from round and strong wires. From round wires, therope can be twisted in many ways using wires of different or equalthickness. In ropes applicable with the invention, the wire thickness isbelow 0.4 mm on an average. Well applicable ropes made from strong wiresare those in which the average wire thickness is below 0.3 mm or evenbelow 0.2 mm. For instance, thin-wired and strong 4 mm ropes can betwisted relatively economically from wires such that the mean wirethickness in the finished rope is in the range of 0.15 . . . 0.25 mm,while the thinnest wires may have a thickness as small as only about 0.1mm. Thin rope wires can easily be made very strong. The inventionemploys rope wires having a strength of over 2000 N/mm². A suitablerange of rope wire strength is 2300-2700 N/mm². In principle, it ispossible to use rope wires as strong as about 3000 N/mm or even more.

By increasing the contact angle using a diverting pulley, the gripbetween the traction sheave and the hoisting ropes can be improved.Therefore, it is possible to reduce the weight of the car andcounterweight and their size can be reduced as well, thus increasing thespace saving potential of the elevator. Alternatively or at the sametime, it is possible to reduce the weight of the elevator car inrelation to the weight of the counterweight. A contact angle of over180° between the traction sheave and the hoisting rope is achieved byusing one or more auxiliary diverting pulleys.

A preferred embodiment of the elevator of the invention is an elevatorwith machine above without machine room, the drive machine of whichcomprises a coated traction sheave and which uses thin hoisting ropes ofsubstantially round cross-section. The contact angle between thehoisting ropes of the elevator and the traction sheave is larger than180°. The elevator comprises a unit comprising a drive machine, atraction sheave and a diverting pulley fitted at a correct anglerelative to the traction sheave, all this equipment being fitted on amounting base. The unit is secured to the elevator guide rails.

In the following, the invention will be described in detail by the aidof a few examples of its embodiments with reference to the attacheddrawings, wherein

FIG. 1 presents a diagram representing a traction sheave elevatoraccording to the invention,

FIG. 2 presents a diagram representing another traction sheave elevatoraccording to the invention,

FIG. 3 presents a rope sheave applying the invention,

FIG. 4 presents a coating solution according to the invention,

FIG. 5 a presents a steel wire rope used in the invention,

FIG. 5 b presents another steel wire rope used in the invention,

FIG. 5 c presents a third steel wire rope used in the invention, and

FIG. 6 presents a diagram of a rope pulley placement in an elevator caraccording to the invention,

FIG. 7 presents a diagrammatic view of a traction sheave elevatoraccording to the invention,

FIG. 8 presents a diagrammatic view of a traction sheave elevatoraccording to the invention,

FIG. 9 presents a diagrammatic view of a traction sheave elevatoraccording to the invention,

FIGS. 10 present traction sheave roping solutions according to theinvention, and

FIG. 11 presents an embodiment according to the invention.

FIG. 1 is a diagrammatic representation of the structure of an elevator.The elevator is preferably an elevator without machine room, with adrive machine 6 placed in the elevator shaft. The elevator shown in thefigure is a traction sheave elevator with machine above. The passage ofthe hoisting ropes 3 of the elevator is as follows: One end of the ropesis immovably fixed to an anchorage 13 located in the upper part of theshaft above the path of a counterweight 2 moving along counterweightguide rails 11. From the anchorage, the ropes run downward and arepassed around diverting pulleys 9 suspending the counterweight, whichdiverting pulleys 9 are rotatably mounted on the counterweight 2 andfrom which the ropes 3 run further upward via the rope grooves ofdiverting pulley 15 to the traction sheave 7 of the drive machine 6,passing around the traction sheave along rope grooves on the sheave.From the traction sheave 7, the ropes 3 run further downward back todiverting pulley 15, passing around it along the rope grooves andreturning then back up to the traction sheave 7, over which the ropesrun in the traction sheave rope grooves. From the traction sheave 7, theropes 3 go further downwards via the rope grooves of diverting pulley 15to the elevator car 1 moving along the car guide rails 10 of theelevator, passing under the car via diverting pulleys 4 used to suspendthe elevator car on the ropes, and going then upward again from theelevator car to an anchorage 14 in the upper part of the elevator shaft,to which anchorage the second end of the ropes 3 is immovably fixed.Anchorage 13 in the upper part of the shaft, the traction sheave 7 andthe diverting pulley 9 suspending the counterweight on the ropes arepreferably so disposed in relation to each other that both the ropeportion going from the anchorage 13 to the counterweight 2 and the ropeportion going from the counterweight 2 to the traction sheave 7 aresubstantially parallel to the path of the counterweight 2. Similarly, asolution is preferred in which anchorage 14 in the upper part of theshaft, the traction sheave 7, diverting pulley 15 and the divertingpulleys 4 suspending the elevator car on the ropes are so disposed inrelation to each other that the rope portion going from the anchorage 14to the elevator car 1 and the rope portion going from the elevator car 1via diverting pulley 15 to the traction sheave 7 are substantiallyparallel to the path of the elevator car 1. With this arrangement, noadditional diverting pulleys are needed to define the passage of theropes in the shaft. The roping arrangement between the traction sheave 7and the diverting pulley 15 is referred to as Double Wrap roping,wherein the hoisting ropes are wrapped around the traction

-   -   sheave two and/or more times. In this way, the contact angle can        be increased in two and/or more stages. For example, in the        embodiment presented in FIG. 1, a contact angle of 180°+180°,        i.e. 360° between the traction sheave 7 and the hoisting ropes 3        is achieved. Double Wrap roping can be arranged in other ways,        too, e.g. by placing the diverting pulley on the side of the        traction sheave, in which case, as the hoisting ropes are passed        twice around the traction sheave, a contact angle of        180°+90°=270° is obtained, or by placing the diverting pulley at        some other appropriate position. The rope suspension acts in a        substantially centric manner on the elevator car 1, provided        that the rope pulleys 4 supporting the elevator car are mounted        substantially symmetrically relative to the vertical center line        passing via the center of gravity of the elevator car 1. A        preferable solution is to dispose the traction sheave 7 and the        diverting pulley 15 in such a way that the diverting pulley 15        will also function as a guide of the hoisting ropes 3 and as a        damping pulley.

The drive machine 6 placed in the elevator shaft is preferably of a flatconstruction, in other words, the machine has a small thicknessdimension as compared with its width and/or height, or at least themachine is slim enough to be accommodated between the elevator car and awall of the elevator shaft. The machine may also be placed differently,e.g. by disposing the slim machine partly or completely between animaginary extension of the elevator car and a shaft wall. The elevatorshaft is advantageously provided with equipment required for the supplyof power to the motor driving the traction sheave 7 as well as equipmentfor elevator control, both of which can be placed in a common instrumentpanel 8 or mounted separately from each other or integrated partly orwholly with the drive machine 6. The drive machine may be of a geared orgearless type. A preferable solution is a gearless machine comprising apermanent magnet motor. Another advantageous solution is to build acomplete unit comprising both an elevator drive machine with a tractionsheave and one or more diverting pulleys with bearings in a correctoperating angle relative to the traction sheave. The operating angle isdetermined by the roping used between the traction sheave an thediverting pulley/pulleys, which defines the way in which the mutualpositions and angle between the traction sheave and divertingpulley/diverting pulleys relative to each other are fitted in the unit.This unit can be mounted in place as a unitary aggregate in the same wayas a drive machine. The drive machine may be fixed to a wall of theelevator shaft, to the ceiling, to a guide rail or guide rails or tosome other structure, such as a beam or frame. In the case of anelevator with machine below, a further possibility is to mount themachine on the bottom of the elevator shaft. FIG. 1 illustrates theeconomical 2:1 suspension, but the invention can also be implemented inan elevator using a 1:1 suspension ratio, in other words, in an elevatorin which the hoisting ropes are connected directly to the counterweightand elevator car without diverting pulleys. Other suspensionarrangements are also possible in an implementation of the invention.For example, an elevator according to the invention can be implementedusing a suspension ratio of 3:1, 4:1 or even higher suspension ratios.The counterweight and the elevator car may also be suspended in suchmanner that the counterweight is suspended using a suspension ratio ofn:1 while the elevator car is suspended with a suspension ratio of m:1,where m is an integer at least equal to 1 and n is an integer greaterthan m. The elevator presented in the figure has automatic telescopingdoors, but other types of automatic doors or turning doors may also beused within the framework of the invention.

FIG. 2 presents a diagram representing another traction sheave elevatoraccording to the invention. In this elevator, the ropes go upward fromthe machine. This type of elevator is generally a traction sheaveelevator with machine below. The elevator car 101 and the counterweight102 are suspended on the hoisting ropes 103 of the elevator. Theelevator drive machine unit 106 is mounted in the elevator shaft,preferably in the lower part of the shaft, a diverting pulley 115 ismounted near the drive machine unit 106, said diverting pulley allowinga sufficiently large contact angle to be achieved between the tractionsheave 107 and the hoisting ropes 103. The hoisting ropes are passed viadiverting pulleys 104,105 provided in the upper part of the elevatorshaft to the car 101 and to the counterweight 102. Diverting pulleys104,105 are placed in the upper part of the shaft and preferablyseparately mounted with bearings on the same axle so that they canrotate independently of each other. By way of example, in the elevatorin FIG. 2, Double Wrap roping is also applied in an elevator withmachine below.

The elevator car 101 and the counterweight 102 move in the elevatorshaft along elevator and counterweight guide rails 110,111 guiding them.

In FIG. 2, the hoisting ropes run as follows: One end of the ropes isfixed to an anchorage 112 in the upper part of the shaft, from where itgoes downward to the counterweight 102. The counterweight is suspendedon the ropes 103 via a diverting pulley 109. From the counterweight, theropes go further upward to a first diverting pulley 105 mounted on anelevator guide rail 110, and from the diverting pulley 105 further viathe rope grooves of diverting pulley 115 to the traction sheave 107driven by the drive machine 106. From the traction sheave, the ropes goagain upwards to diverting pulley 115, and having wrapped around it theygo back to the traction sheave 107. From the traction sheave 107, theropes go again upwards via the rope grooves of diverting pulley 115 todiverting pulley 104, and having wrapped around this pulley they passvia diverting pulleys 108 mounted on the top of the elevator car andthen go further to an anchorage 113 in the upper part of the elevatorshaft, where the other end of the hoisting ropes is fixed. The elevatorcar is suspended on the hoisting ropes 103 by means of diverting pulleys108. In the hoisting ropes 103, one or more of the rope portions betweenthe diverting pulleys or between the diverting pulleys and the tractionsheave or between the diverting pulleys and the anchorages may deviatefrom an exact vertical direction, a circumstance that makes it easy toprovide a sufficient distance between different rope portions or asufficient distance between the hoisting ropes and the other elevatorcomponents. The traction sheave 107 and the hoisting machine 106 arepreferably disposed somewhat aside from the path of the elevator car 101as well as that of the counterweight 102, so they can be easily placedalmost at any height in the-elevator shaft below the diverting pulleys104 and 105. If the machine is not placed directly above or below thecounterweight or elevator car, this will allow a saving in shaft height.In this case, the minimum height of the elevator shaft is exclusivelydetermined on the basis of the length of the paths of the counterweightand elevator car and the safety clearances needed above and below these.In addition, a smaller space at the top or bottom of the shaft will besufficient due to the reduced rope pulley diameters as compared withearlier solutions, depending on how the rope pulleys are mounted on theelevator car and/or on the frame of the elevator car.

FIG. 3 presents a partially sectioned view of a rope pulley 200 applyingthe invention. The rim 206 of the rope pulley is provided with ropegrooves 201, which are covered by a coating 202. Provided in the hub ofthe rope pulley is a space 203 for a bearing used to mount the ropepulley. The rope pulley is also provided with holes 205 for bolts,allowing the rope pulley to be fastened by its side to an anchorage inthe hoisting machine 6, e.g. to a rotating flange, to form a tractionsheave 7, so that no bearing separate from the hoisting machine isneeded. The coating material used on the traction sheave and the ropepulleys may consist of rubber, polyurethane or a corresponding elasticmaterial that increases friction. The material of the traction sheaveand/or rope pulleys may also be so chosen that, together with thehoisting rope used, it forms a material pair such that the hoisting ropewill bite into the pulley after the coating on the pulley has been wornout. This ensures a sufficient grip between the rope pulley 200 and thehoisting rope 3 in an emergency where the coating 202 has been worn outfrom the rope pulley 200. This feature allows the elevator to maintainits functionality and operational reliability in the situation referredto. The traction sheave and/or the rope pulleys can also be manufacturedin such manner that only the rim 206 of the rope pulley 200 is made of amaterial forming a grip increasing material pair with the hoisting rope3. The use of strong hoisting ropes that are considerably thinner thannormally allows the traction sheave and the rope pulleys to be designedto considerably smaller dimensions and sizes than when normal-sizedropes are used. This also makes it possible to use a motor of a smallersize with a lower torque as the drive motor of the elevator, which leadsto a reduction in the acquisition costs of the motor. For example, in anelevator according to the invention designed for a nominal load below1000 kg, the traction sheave diameter is preferably 120-200 mm, but itmay even be less than this. The traction sheave diameter depends on thethickness of the hoisting ropes used. In the elevator of the invention,the use of a small traction sheave, e.g. in the case of elevators for anominal load below 1000 kg, makes it possible to achieve a machineweight even as low as about one half of the weight of currently usedmachines, which means producing elevator machines weighing 100-150 kg oreven less. In the invention, the machine is understood as comprising atleast the traction sheave, the motor, the machine housing structures andthe brakes.

The weight of the elevator machine and its supporting elements used tohold the machine in place in the elevator shaft is at most about ⅕ ofthe nominal load. If the machine is exclusively or almost exclusivelysupported by one or more elevator and/or counterweight guide rails, thenthe total weight of the machine and its supporting elements may be lessthan about ⅙ or even less than ⅛ of the nominal load. Nominal load of anelevator means a load defined for elevators of a given size. Thesupporting elements of the elevator machine may include e.g. a beam,carriage or suspension bracket used to support or suspend the machineon/from a wall structure or ceiling of the elevator shaft or on theelevator or counterweight guide rails, or clamps used to hold themachine fastened to the sides of the elevator guide rails. It will beeasy to achieve an elevator in which the machine deadweight withoutsupporting elements is below {fraction (1/7)} of the nominal load oreven about {fraction (1/10)} of the nominal load or still less.Basically, the ratio of machine weight to nominal load is given for aconventional elevator in which the counterweight has a weightsubstantially equal to the weight of an empty car plus half the nominalload. As an example of machine weight in the case of an elevator of agiven nominal weight when the fairly common 2:1 suspension ratio is usedwith a nominal load of 630 kg, the combined weight of the machine andits supporting elements may be only 75 kg when the traction sheavediameter is 160 mm and hoisting ropes having a diameter of 4 mm areused, in other words, the total weight of the machine and its supportingelements is about ⅛ of the nominal load of the elevator. As anotherexample, using the same 2:1 suspension ratio, the same 160 mm tractionsheave diameter and the same 4 mm hoisting rope diameter, in the case ofan elevator for a nominal load of about 1000 kg, the total weight of themachine and its supporting elements is about 150 kg, so in this case themachine and its supporting elements have a total weight equaling about ⅙of the nominal load. As a third example, let us consider an elevatordesigned for a nominal load of 1600 kg. In this case, when thesuspension ratio is 2:1, the traction sheave diameter 240 mm and thehoisting rope diameter 6 mm, the total weight of the machine and itssupporting elements will be about 300 kg, i.e. about {fraction (1/7)} ofthe nominal load. By varying the hoisting rope suspension arrangements,it is possible to reach a still lower total weight of the machine andits supporting elements. For example, when a 4:1 suspension ratio, a 160mm traction sheave diameter and a 4 mm hoisting rope diameter are usedin an elevator designed for a nominal load of 500 kg, a total weight ofhoisting machine and its supporting elements of about 50 kg will beachieved. In this case, the total weight of the machine and itssupporting elements is as small as only about {fraction (1/10)} of thenominal load.

FIG. 4 presents a solution in which the rope groove 301 is in a coating302, which is thinner at the sides of the rope groove than at thebottom. In such a solution, the coating is placed in a basic groove 320provided in the rope pulley 300 so that deformations produced in thecoating by the pressure imposed on it by the rope will be small andmainly limited to the rope surface texture sinking into the coating.Such a solution often means in practice that the rope pulley coatingconsists of rope groove-specific sub-coatings separate from each other,but considering manufacturing or other aspects it may be appropriate todesign the rope pulley coating so that it extends continuously over anumber of grooves.

By making the coating thinner at the sides of the groove than at itsbottom, the strain imposed by the rope on the bottom of the rope groovewhile sinking into the groove is avoided or at least reduced. As thepressure cannot be discharged laterally but is directed by the combinedeffect of the shape of the basic groove 320 and the thickness variationof the coating 302 to support the rope in the rope groove 301, lowermaximum surface pressures acting on the rope and the coating are alsoachieved. One method of making a grooved coating 302 like this is tofill the round-bottomed basic groove 320 with coating material and thenform a half-round rope. groove 301 in this coating material in the basicgroove. The shape of the rope grooves is well supported and theload-bearing surface layer under the rope provides a better resistanceagainst lateral propagation of the compression stress produced by theropes. The lateral spreading or rather adjustment of the coating causedby the pressure is promoted. by thickness and elasticity of the coatingand reduced by hardness and eventual reinforcements of the coating. Thecoating thickness on the bottom of the rope groove can be made large,even as large as half the rope thickness, in which case a hard andinelastic coating is needed. On the other hand, if a coating thicknesscorresponding to only about one tenth of the rope thickness is used,then the coating material may be clearly softer. An elevator for eightpersons could be implemented using a coating thickness at the bottom ofthe groove equal to about one fifth of the rope thickness if the ropesand the rope load are chosen appropriately. The coating thickness shouldequal at least 2-3 times the depth of the rope surface texture formed bythe surface wires of the rope. Such a very thin coating, having athickness even less than the thickness of the surface wire of the rope,will not necessarily endure the strain imposed on it. In practice, thecoating must have a thickness larger than this minimum thickness becausethe coating will also have to receive rope surface variations rougherthan the surface texture. Such a rougher area is formed e.g. where thelevel differences between rope strands are larger than those betweenwires. In practice, a suitable minimum coating thickness is about 1-3times the surface wire thickness. In the case of the ropes normally usedin elevators, which have been designed for a contact with a metallicrope groove and which have a thickness of 8-10 mm, this thicknessdefinition leads to a coating at least about 1 mm thick. Since a coatingon the traction sheave, which causes more rope wear than the other ropepulleys of the elevator, will reduce rope wear and therefore also theneed to provide the rope with thick surface wires, the rope can be madesmoother. Rope smoothness can naturally be improved by coating the ropewith a material suited for this purpose, such as e.g. polyurethane orequivalent. The use of thin wires allows the rope itself to be madethinner, because thin steel wires can be manufactured from a strongermaterial than thicker wires. For instance, using 0.2 mm wires, a 4 mmthick elevator hoisting rope of a fairly good construction can beproduced. Depending on the thickness of the hoisting rope used and/or onother reasons, the wires in the steel wire rope may preferably have athickness between 0.15 mm and 0.5 mm, in which range there are readilyavailable steel wires with good strength properties in which even anindividual wire has a sufficient wear resistance and a sufficiently lowsusceptibility to damage. In the above, -ropes made of round steel wireshave been discussed. Applying the same principles, the ropes can bewholly or partly twisted from non-round profiled wires. In this case,the cross-sectional areas of the wires are preferably substantially thesame as for round wires, i.e. in the range of 0.015 mm²-0.2 mm. Usingwires in this thickness range, it will be easy to produce steel wireropes having a wire strength above about 2000 N/m² and a wirecross-section of 0.015 mm²-0.2 mm² and comprising a largecross-sectional area of steel material in relation to thecross-sectional area of the rope, as is achieved e.g. by using theWarrington construction. For the implementation of the invention,particularly well suited are ropes having a wire strength in the rangeof 2300 N/m²-2700 N/mm², because such ropes have a very large bearingcapacity in relation to rope thickness while the high hardness of thestrong wires involves no substantial difficulties in the use of the ropein elevators. A traction sheave coating well suited for such a rope isalready clearly below 1 mm thick. However, the coating should be thickenough to ensure that it will not be very easily scratched away orpierced e.g. by an occasional sand grain or similar particle that mayhave got between the rope groove and the hoisting rope. Thus, adesirable minimum coating thickness, even when thin-wire hoisting ropesare used, would be about 0.5 . . . 1 mm. For hoisting ropes having smallsurface wires and an otherwise relatively smooth surface, a coatinghaving a thickness of the form A+Bcosa is well suited. However, such acoating is also applicable to ropes whose surface strands meet the ropegroove at a distance from each other, because if the coating material issufficiently hard, each strand meeting the rope groove is in a wayseparately supported and-the supporting force is the same and/or asdesired. In the formula A+Bcosa, A and B are constants so that A+B isthe coating thickness at the bottom of the rope groove 301 and the anglea is the angular distance from the bottom of the rope groove as measuredfrom the center of curvature of the rope groove cross-section. ConstantA is larger than or equal to zero, and constant B is always larger thanzero. The thickness of the coating growing thinner towards the edges canalso be defined in other ways besides using the formula A+Bcosa so thatthe elasticity decreases towards the edges of the rope groove. Theelasticity in the central part of the rope groove can also be increasedby making an undercut rope groove and/or by adding to the coating on thebottom of the rope groove a portion of different material of specialelasticity, where the elasticity has been increased, in addition toincreasing the material thickness, by the use of a material that issofter than the rest of the coating.

FIG. 5 a, 5 b and 5 c present longitudinal cross-sections of steel wireropes used in the invention. The ropes in these figures contain thinsteel wires 403, a coating 402 on the steel wires and/or partly betweenthe steel wires, and in FIG. 5 a a coating 401 over the steel wires. Therope presented in FIG. 5 b is an uncoated steel wire rope with arubber-like filler added to its interior structure, and FIG. 5 apresents a steel wire rope provided with a coating in addition to afiller added to the internal structure. The rope presented in FIG. 5 chas a non-metallic core 404, which may be a solid or fibrous structuremade of plastic, natural fiber or some other material suited for thepurpose. A fibrous structure will be good if the rope is lubricated, inwhich case lubricant will accumulate in the fibrous core. The core thusacts as a kind of lubricant storage. The steel wire ropes ofsubstantially round cross-section used in the elevator of the inventionmay be coated, uncoated and/or provided with a rubber-like filler, suchas e.g. polyurethane or some other suitable filler, added to theinterior structure of the rope and acting as a kind of lubricantlubricating the rope and also balancing the pressure between wires andstrands. The use of a filler makes it possible to achieve a rope thatneeds no lubrication, so its surface can be dry. The coating used in thesteel wire ropes may be made of the same or nearly the same material asthe filler or of a material that is better suited for use as a coatingand has properties, such as friction and wear resistance properties,that are better suited to the purpose than a filler. The coating of thesteel wire rope may also be so implemented that the coating materialpenetrates partially into the rope or through the entire thickness ofthe rope, giving the rope the same properties as the filler mentionedabove. The use of thin and strong steel wire ropes according to theinvention is possible because the steel wires used are wires of specialstrength, allowing the ropes to be made substantially thin as comparedwith steel wire ropes used before. The ropes presented in FIG. 5 a and 5b are steel wire ropes having a diameter of about 4 mm. For example,when a 2:1 suspension ratio is used, the thin and strong steel wireropes of the invention preferably have a diameter of about 2.5-5 mm inelevators for a nominal load below 1000 kg, and preferably about 5-8 mmin elevators for a nominal load above 1000 kg. In principle, it ispossible to use ropes thinner than this, but in this case a large numberof ropes will be needed. Still, by increasing the suspension ratio,ropes thinner than those mentioned above can be used for correspondingloads, and at the same time a smaller and lighter elevator machine canbe achieved.

FIG. 6 illustrates the manner in which a rope pulley 502 connected to ahorizontal beam 504 comprised in the structure supporting the elevatorcar 501 is placed in relation to the beam 504, said rope pulley beingused to support the elevator car and associated structures. The ropepulley 502 presented in the figure may have a diameter equal to or lessthan the height of the beam 504 comprised in the structure. The beam 504supporting the elevator car 501 may be located either below or above theelevator car. The rope pulley 502 may be placed completely or partiallyinside the beam 504, as shown in the figure. The hoisting ropes 503 ofthe elevator in the figure run as follows: The hoisting ropes 503 cometo the coated rope pulley 502 connected to the beam 504 comprised in thestructure supporting the elevator car 501, from which pulley thehoisting rope runs further, protected by the beam, e.g. in a hollow 506inside the beam, under the elevator car and goes then further via asecond rope pulley placed on the other side of the elevator car. Theelevator car 501 rests on the beam 504 comprised in the structure, onvibration absorbers 505 placed between them. The beam 504 also acts as arope guard for the hoisting rope 503. The beam 504 may be a C-, U-, I-,Z-section beam or a hollow beam or equivalent.

FIG. 7 presents a diagrammatic illustration of the structure of anelevator according to the invention. The elevator is preferably anelevator without machine room, with a drive machine 706 placed in theelevator shaft. The elevator shown in the figure is a traction sheaveelevator with machine above. The passage of the hoisting ropes 703 ofthe elevator is as follows: One end of the ropes is immovably fixed toan anchorage 713 located in the upper part of the shaft above the pathof a counterweight 702 moving along counterweight guide rails 711. Fromthe anchorage, the ropes run downwards to diverting pulleys 709suspending the counterweight, which are rotatably mounted on thecounterweight 702 and from which the ropes 703 run further upward viathe rope grooves of diverting pulley 715 to the traction sheave 707 ofthe drive machine 706, passing around the traction sheave along the ropegrooves on the sheave. From the traction sheave 707, the ropes 703 runfurther downwards back to diverting pulley 715, wrapping around it alongthe rope grooves of the diverting pulley and returning then back up tothe traction sheave 707, over which the ropes run in the traction sheaverope grooves. From the traction sheave 707, the ropes 703 go furtherdownwards via the rope grooves of the diverting pulley to the elevatorcar 701 moving along the car guide rails 710 of the elevator, passingunder the car via diverting pulleys 704 used to suspend the elevator caron the ropes, and going then upwards again from the elevator car to ananchorage 714 in the upper part of the elevator shaft, to whichanchorage the second end of the ropes 703 is immovably fixed. Anchorage713 in the upper part of the shaft, the traction sheave 707, divertingpulley 715 and the diverting pulley 709 suspending the counterweight onthe ropes are preferably so disposed in relation to each other that boththe rope portion going from the anchorage 713 to the counterweight 702and the rope portion going from the counterweight 702 via divertingpulley 715 to the traction sheave 707 are substantially parallel to thepath of the counterweight 702. Similarly, a solution is preferred inwhich the anchorage 714 in the upper part of the shaft, the tractionsheave 707, diverting pulleys 715,712 and the diverting pulleys 704suspending the elevator car on the ropes are so disposed in relation toeach other that the rope portion going from the anchorage 714 to theelevator car 701 and the rope portion going from the elevator car 701via diverting pulley 715 to the traction sheave 707 are substantiallyparallel to the path of the elevator car 701. With this arrangement, noadditional diverting pulleys are needed to define the passage of theropes in the shaft. The roping arrangement between the traction sheave707 and the diverting pulley 715 is referred to as Double Wrap roping,wherein the hoisting ropes are wrapped around the traction sheave twoand/or more times. In this way, the contact angle can be increased intwo and/or more stages. For example, in the embodiment presented in FIG.7, a contact angle of 180°+180°, i.e. 360° between the traction sheave707 and the hoisting ropes 703 is achieved. The rope suspension acts ina substantially centric manner on the elevator car 701, provided thatthe rope pulleys 704 suspending the elevator car are mountedsubstantially symmetrically relative to the vertical center line passingvia the center of gravity of the elevator car 701. A preferable solutionis to dispose the traction sheave 707 and the diverting pulley 715 insuch a way that the diverting pulley 715 will also function as a guideof the hoisting ropes 703 and as a damping pulley.

The drive machine 706 placed in the elevator shaft is preferably of flatconstruction, in other words, the machine has a small thicknessdimension as compared with its width and/or height, or at least themachine is slim enough to be accommodated between the elevator car and awall of the elevator shaft. The machine may also be placed differently,e.g. by disposing the slim machine partly or completely between animaginary extension of the elevator car and a shaft wall. The elevatorshaft is advantageously provided with equipment required for the supplyof power to the motor driving the traction sheave 707 as well asequipment needed for elevator control, both of which can be placed in acommon instrument panel 708 or mounted separately from each other orintegrated partly or wholly with the drive machine 706. The drivemachine may be of geared or gearless type. A preferable solution is agearless machine comprising a permanent magnet motor. Anotheradvantageous solution is to build a complete unit comprising both theelevator drive machine 706 and the diverting pulley 715 and itsbearings, which is used to increase the contact angle, in a correctoperating angle relative to the traction sheave 707, which unit can bemounted in place as a unitary aggregate in the same way as a drivemachine. The drive machine may be fixed to a wall of the elevator shaft,to the ceiling, to a guide rail or guide rails or to some otherstructure, such as a beam or frame. The diverting pulley/divertingpulleys to be placed near the drive machine to increase the operatingangle can be mounted in the same way. In the case of an elevator withmachine below, a further possibility is to mount the above-mentionedcomponents on the bottom of the elevator shaft. In Double Wrap roping,when diverting pulley 715 is of substantially equal size with thetraction sheave 707, diverting pulley 715 can also function as a dampingwheel. In this case, the ropes going from the traction sheave 707 to thecounterweight 702 and to the elevator car 701 are passed via the ropegrooves of the diverting pulley 715 and the rope deflection caused bythe diverting pulley is very small. It could be said that the ropescoming from the traction sheave only touch the diverting pulleytangentially. Such tangential contact serves as a solution damping thevibrations of outgoing ropes and it can applied in other ropingsolutions as well. An example of these other roping solutions is SingleWrap (SW) roping, where the diverting pulley is of substantially equalsize with the traction sheave of the drive machine and where a divertingpulley used for tangential rope contact as described above. In SW ropingaccording to the example, the ropes wrap around the traction sheave onlyonce, with a contact angle of about 180° between the rope and thetraction sheave, the diverting pulley is only used as a means ofproducing a tangential contact as described above and the divertingpulley functions as a rope guide and as a damping wheel for the dampingof vibrations. The suspension ratio of the elevator is of no importancewith respect to the application of SW roping described in the example;instead, it can be used in connection with any suspension ratio. Theembodiment using SW roping as described in the example may have aninventive value in itself, at least in regard of damping. The divertingpulley 715 may also be of substantially different size than the tractionsheave, in which case it functions as a diverting pulley increasing thecontact angle and not as a damping wheel. FIG. 7 presents an elevatoraccording to the invention that uses a suspension ratio of 4:1. Theinvention can also be implemented using other suspension arrangements.For example, an elevator according to the invention can be implementedusing a suspension ratio of 1:1, 2:1, 3:1 or even suspension ratioshigher than 4:1. The elevator presented in the figure has automatictelescoping doors, but other types of automatic doors or turning doorsmay also be used within the framework of the invention.

FIG. 8 presents a diagrammatic illustration of the structure of anelevator according to the invention. The elevator is preferably anelevator without machine room, with a drive machine 806 placed in theelevator shaft. The elevator shown in the figure is a traction sheaveelevator with machine above. The passage of the hoisting ropes 803 ofthe elevator is as follows: One end of the ropes is immovably fixed toan anchorage 813 located in the upper part of the shaft above the pathof a counterweight 802 moving along counterweight guide rails 811. Fromthe anchorage, the ropes run downwards to diverting pulleys 809suspending the counterweight, which are rotatably mounted on thecounterweight .802 and from which the ropes 803 run further upward viathe rope grooves of diverting pulley 815 to the traction sheave 807 ofthe drive machine 806, wrapping around the traction sheave along therope grooves on the sheave. From the traction sheave 807, the ropes 803run further downwards, going crosswise relative to the upwards goingropes, and further via the rope grooves of the diverting pulley to theelevator car 801 moving along the car guide rails 810 of the elevator,passing under the car via diverting pulleys 804 used to suspend theelevator car on the ropes, and going then upwards again from theelevator car to an anchorage 814 in the upper part of the elevatorshaft, to which anchorage the second end of the ropes 803 is immovablyfixed. Anchorage 813 in the upper part of the shaft, the traction sheave807, diverting pulley 815 and the diverting pulley 809 suspending thecounterweight on the ropes are preferably so disposed in relation toeach other that both the rope portion going from the anchorage 813 tothe counterweight 802 and the rope portion going from the counterweight802 via diverting pulley 815 to the traction sheave 807 aresubstantially parallel to the path of the counterweight 802. Similarly,a solution is preferred in which the anchorage 814 in the upper part ofthe shaft, the traction sheave 807, diverting pulley 815 and thediverting pulleys 804 suspending the elevator car on the ropes are sodisposed in relation to each other that the rope portion going from theanchorage 814 to the elevator car 801 and the rope portion going fromthe elevator car 801 via diverting pulley 815 to the traction sheave 807are substantially parallel to the path of the elevator car 801. Withthis arrangement, no additional diverting pulleys are needed to definethe passage of the ropes in the shaft. This roping arrangement betweenthe traction sheave 807 and the diverting pulley 815 can be referred toas X Wrap (XW) roping, while Double Wrap (DW) roping, Single Wrap (SW)roping and Extended Wrap (ESW) roping are previously known concepts. InX Wrap roping, the ropes are caused to wrap around the traction sheavewith a large contact angle. For example, in the case illustrated in FIG.8, a contact angle of well over 180°, i.e. about 270° between thetraction sheave 807 and the hoisting ropes 803 is achieved. X Wraproping presented in the figure can also be arranged in another way, e.g.by providing two diverting pulleys at appropriate positions near thedrive machine. Diverting pulley 815 has been fitted in a positiondesigned to form an angle relative to the traction sheave 807 such thatthe ropes will run crosswise in a manner known in itself so that theropes are not damaged. The rope suspension acts in a substantiallycentric manner on the elevator car 801, provided that the rope pulleys804 suspending the elevator car are mounted substantially symmetricallyrelative to the vertical center line passing via the center of gravityof the elevator car 801.

The drive machine 806 placed in the elevator shaft is preferably of flatconstruction, in other words, the machine has a small thicknessdimension as compared with its width and/or height, or at least themachine is slim enough to be accommodated between the elevator car and awall of the elevator shaft. The machine may also be placed differently,e.g. by disposing the slim machine partly or completely between animaginary extension of the elevator car and a shaft wall. The elevatorshaft is advantageously provided with equipment required for the supplyof power to the motor driving the traction sheave 807 as well asequipment needed for elevator control, both of which can be placed in acommon instrument panel 808 or mounted separately from each other orintegrated partly or wholly with the drive machine 806. The drivemachine may be of geared or gearless type. A preferable solution is agearless machine comprising a permanent magnet motor. Anotheradvantageous solution is to build a complete unit comprising both theelevator drive machine 806 and the diverting pulley 815 and itsbearings, which is used to increase the contact angle, in a correctoperating angle relative to the traction sheave 807, which unit can bemounted in place as a unitary aggregate in the same way as a drivemachine. Using a complete unit means less need for rigging duringinstallation. X Wrap roping can also be implemented by mounting adiverting pulley directly on the drive machine. The drive machine may befixed to a wall of the elevator shaft, to the ceiling, to a guide railor guide rails or to some other structure, such as a beam or frame. Thediverting pulley to. be placed near the drive machine to increase theoperating angle can be mounted in the same way. In the case of anelevator with machine below, a further possibility is to mount theabove-mentioned components on the bottom of the elevator shaft. FIG. 8illustrates the economical 2:1 suspension, but the invention can also beimplemented in an elevator with 1:1 suspension ratio, in other words, inan elevator with the hoisting ropes connected directly to thecounterweight and elevator car without a diverting pulley. The inventioncan also be implemented using other suspension arrangements. Forexample, an elevator according to the invention can be implemented usinga suspension ratio of 3:1, 4:1 or even higher suspension ratios. Theelevator presented in the figure has automatic telescoping doors, butother types of automatic doors or turning doors may also be used withinthe framework of the invention.

FIG. 9 presents a diagrammatic illustration of the structure of anelevator according to the invention. The elevator is preferably anelevator without machine room, with a drive machine 906 placed in theelevator shaft. The elevator shown in the figure is a traction sheaveelevator with machine above. The passage of the hoisting ropes 903 ofthe elevator is as follows: One end of the ropes is immovably fixed toan anchorage 913 located in the upper part of the shaft above the pathof a counterweight 902 moving along counterweight guide rails 911. Fromthe anchorage, the ropes run downwards to diverting pulleys. 909suspending the counterweight, which are rotatably mounted on thecounterweight 902 and from which diverting pulleys 909 the ropes 903 runfurther upward to the traction sheave 907 of the drive machine 906,wrapping around the traction sheave along the rope grooves on thesheave. From,the traction sheave 907, the ropes 903 run furtherdownwards, going crosswise relative to the upwards going ropes, andfurther to diverting pulley 915, wrapping around it along the ropegrooves of the diverting pulley 915. From the diverting pulley 915, theropes go further downwards to the elevator car 901 moving along the carguide rails 910 of the elevator, passing under the car via divertingpulleys 904 used to suspend the elevator car on the ropes, and goingthen upwards again from the elevator car to an anchorage 914 in theupper part of the elevator shaft, to which anchorage the second end ofthe ropes 903 is immovably fixed. Anchorage 913 in the upper. part ofthe shaft, the traction sheave 907 and the diverting pulley 909suspending the counterweight on the ropes are preferably so disposed inrelation to each other that both the rope portion going from theanchorage 913 to the counterweight 902 and the rope portion going fromthe counterweight 902 to the traction sheave 907 are substantiallyparallel to the path of the counterweight 902. Similarly, a solution ispreferred in which the anchorage 914 in the upper part. of the shaft,the traction sheave 907, diverting pulley 915 and the diverting pulleys904 suspending the elevator car on the ropes are so disposed in relationto each other that the rope portion going from the anchorage 914 to theelevator car 901 and the rope portion going from the elevator car 901via diverting pulley 915 to the traction sheave 907 are substantiallyparallel to the path of the elevator car 901. With this arrangement, noadditional diverting pulleys are needed to define the passage of theropes in the shaft. This roping arrangement between the traction sheave907 and the diverting pulley 915 can be referred to as Extended SingleWrap roping. In Extended Single Wrap roping, by using a divertingpulley, the hoisting ropes are caused to wrap around the traction sheavewith a larger contact angle. For example, in the case illustrated inFIG. 9, a contact angle of well over 180°, i.e. about 270° between thetraction sheave 907 and the hoisting ropes 903 is achieved. ExtendedSingle Wrap roping presented in the figure can also be arranged inanother way, e.g. by disposing the drive machine and the divertingpulley in another way in relation to each other, e.g. the other wayround relative to each other than in the case presented in FIG. 9.Diverting pulley 915 has been fitted in a position designed to form anangle relative to the traction sheave 907 such that the ropes will runcrosswise in a manner known in itself so that the ropes are not damaged.The rope suspension acts in a substantially centric manner on theelevator car 901, provided that the rope pulleys 904 suspending theelevator car are mounted substantially symmetrically relative to thevertical center line passing via the center of gravity of the elevatorcar 901. In the solution represented by FIG. 9, the drive machine 906can preferably be placed e.g. in the free space above the counterweight,thereby increasing the space saving potential of the elevator.

The drive machine 906 placed in the elevator shaft is preferably of flatconstruction, in other words, the machine has a small thicknessdimension as compared with its width and/or height, or at least themachine is slim enough to be accommodated between the elevator car and awall of the elevator shaft. The machine may also be placed differently,e.g. by disposing the slim machine partly or completely between animaginary extension of the elevator car and a shaft wall. The elevatorshaft is advantageously provided with equipment required for the supplyof power to the motor driving the traction sheave 907 as well asequipment needed for elevator control, both of which can be placed in acommon instrument panel 908 or mounted separately from each other orintegrated partly or wholly with the drive machine. 906. The drivemachine may be of geared or gearless type. A preferable solution is agearless machine comprising a permanent magnet motor. Anotheradvantageous solution is to build a complete unit comprising both theelevator drive machine 906 and/or the diverting pulley/diverting pulleys915 with their bearings, mounted in a correct operating angle relativeto the traction sheave 907 to increase the contact angle, all thisequipment being ready fitted on a mounting base, which unit can bemounted in place as a unitary aggregate in the same way as a drivemachine. Using a unitary aggregate solution reduces the need for riggingat installation time. The drive machine may be fixed to a wall of theelevator shaft, to the ceiling, to a guide rail or guide rails or tosome other structure, such as a beam or frame. The diverting pulley tobe placed near the drive machine to increase the operating angle can bemounted in the same way. In the case of an elevator with machine below,a further possibility is to mount the above-mentioned components on thebottom of the elevator shaft. FIG. 9 illustrates the economical 2:1suspension, but the invention can also be implemented in an elevatorwith 1:1 suspension ratio, in other words, in an elevator with thehoisting ropes connected directly to the counterweight and elevator carwithout a diverting pulley. The invention can also be implemented usingother suspension arrangements. For example, an elevator according to theinvention can be implemented using a suspension ratio of 3:1, 4:1 oreven higher suspension ratios. The elevator presented, in the figure hasautomatic telescoping doors, but other types of automatic doors orturning doors may also be used within the framework of the invention.FIGS. 10 a, 10 b, 10 c, 10 d, 10 e, 10 f and 10 g present somevariations of the roping arrangements according to the invention thatcan be used between the traction sheave 1007 and the diverting pulley1015 to increase the contact angle between the ropes 1003 and thetraction sheave 1007, in which arrangements the ropes 1003 go downwardsfrom the drive machine 1006 towards the elevator car and counterweight.These roping arrangements make it possible to increase the: contactangle between the hoisting rope 1003 and the traction sheave 1007. Inthe invention, contact angle a refers to the length of the arc ofcontact between the traction sheave and the hoisting rope. The magnitudeof the contact angle α may be expressed e.g. in degrees, as is done inthe invention, but it is also possible to express the magnitude of thecontact angle in other terms, e.g. in radians or equivalent. The contactangle α is presented in greater detail in FIG. 10 a. In the otherfigures, the contact angle α is not expressly indicated, but it can beseen from the other figures as well without specific description.

The roping arrangements presented in FIG. 10 a, 10 b, 10 c representsome variations of the X Wrap roping described above. In the arrangementpresented in FIG. 10 a, the ropes 1003 come via diverting pulley 1015,wrapping around it along rope grooves, to the traction sheave 1007, overwhich the ropes pass along its rope grooves and then go further back tothe diverting pulley 1015, passing crosswise with respect to the ropeportion coming from the diverting pulley, and continuing their passagefurther. Crosswise passage of the ropes 1003 between the divertingpulley 1015 and the traction sheave 1007 can be implemented e.g. byhaving the diverting pulley fitted at such an angle with respect to thetraction sheave that the ropes will cross each other in a manner knownin itself so that the ropes 1003 are not damaged. In FIG. 10 a, thecontact angle α between the ropes 1003 and the traction sheave 1007 isrepresented by the shaded area. The magnitude of the contact angle α inthis figure is about 310°. The size of the diameter of the divertingpulley can be used as a means of determining the distance of suspensionthat is to be provided between the diverting pulley 1015 and thetraction sheave 1007. The magnitude of the contact angle can be variedby varying the distance between the diverting pulley 1015 and thetraction sheave 1007. The magnitude of the angle α can also be varied byvarying the diameter of the diverting pulley and/or by varying thediameter of the traction sheave and also by varying the relation betweenthe diameters of the diverting pulley and the traction sheave. FIG. 10 band 10 c present an example of implementing a corresponding XW ropingarrangement using two diverting pulleys.

The roping arrangements presented in FIG. 10 d and 10 e are differentvariations of the above-mentioned Double Wrap roping. In the ropingarrangement in FIG. 10 d, the ropes run via the rope grooves ofdiverting pulley 1015 to the traction sheave traction sheave 1007 of thedrive machine 1006, passing over it along the rope grooves of thetraction sheave. From the traction sheave 1007, the ropes 1003 gofurther downwards back to diverting pulley 1015, wrapping around italong the rope grooves of the diverting pulley and returning then backto the traction sheave 1007, over which the ropes run in the ropegrooves of the traction sheave. From the traction sheave 1007, the ropes1003 run further downwards via the rope grooves of the diverting pulley.In the roping arrangement presented in the figure, the hoisting ropesare caused to wrap around the traction sheave twice and/or more times.By these means, the contact angle can be increased in two and/or morestages. For example, in the case presented in FIG. 10 d, a contact angleof 180°+180° between the traction sheave 1007 and the ropes 1003 isachieved. In Double Wrap roping, when the diverting pulley 1015 issubstantially of equal size with the traction sheave 1007, the divertingpulley 1015 also functions as a damping wheel. In this case, the ropesgoing from the traction sheave 1007 to the counterweight and elevatorcar pass via the rope grooves of the diverting pulley 1015 and the ropedeflection produced by the diverting pulley is very small. It could besaid that the ropes coming from the traction sheave only touch thediverting pulley tangentially. Such tangential contact serves as asolution damping the vibrations of outgoing ropes and it can applied inother roping arrangements as well. In this case, the diverting pulley1015 also functions as a rope guide. The ratio of the diameters of thediverting pulley and traction sheave can be varied by varying thediameters of the diverting pulley and/or traction sheave. This can beused as a means of defining the magnitude of the contact angle andfitting it to a desired magnitude. By using DW roping, forward bendingof the rope 1003 is achieved, which means that the rope 1003 is in DWroping is bent in the same direction on the diverting pulley 1015 and onthe traction sheave 1007. DW roping can also be implemented in otherways, such as e.g. the way illustrated in FIG. 10 e, where the divertingpulley 1015 is disposed on the side of the traction sheave 1007. In thisroping arrangement, the ropes 1003 are passed in a manner correspondingto FIG. 10 d, but in this case a contact angle of 180°+90°, i.e. 270° isobtained. If the diverting pulley 1015 is placed on the side of thetraction sheave in the case of DW roping, greater demands are imposed onthe bearings and mounting of the diverting pulley because it is exposedto greater stress and load forces than in the embodiment presented inFIG. 10 d.

FIG. 10 f presents an embodiment of the invention applying ExtendedSingle Wrap roping as mentioned above. In the roping arrangementpresented in the figure, the ropes 1003 run to the traction sheave 1007of the drive machine 1006, wrapping around it along the rope grooves ofthe traction sheave. From the traction sheave 1007, the ropes 1003 gofurther downwards, running crosswise relative to the upwards going ropesand further to diverting pulley 1015, passing over it along the ropegrooves of the diverting pulley 1015. From the diverting pulley 1015,the ropes 1003 run further on. In Extended Single Wrap roping, by usinga diverting pulley, the hoisting ropes are caused to wrap around thetraction sheave with a larger contact angle than in ordinary Single Wraproping. For example, in the case illustrated in FIG. 10 f, a contactangle of about 270° between the ropes 1003 and the traction sheave 1007is obtained. The diverting pulley 1015 is fitted in position at an anglesuch that the ropes run crosswise in a manner known in itself, so thatthe ropes are not damaged. By virtue of the contact angle achieved usingExtended Single Wrap roping, elevators implemented according to theinvention can use a very light elevator car and the elevator drivemachine can be placed e.g. in the free space above the counterweight,thus allowing freer disposition of other elevator components becausethere is more space available. One possibility of increasing the contactangle is illustrated in FIG. 10 g, where the hoisting ropes do not runcrosswise relative to each other after wrapping around the tractionsheave and/or diverting pulley. By using a roping arrangement like this,it is also possible increase the contact angle between the hoistingropes 1003 and the traction sheave 1007 of the drive machine 1006 to amagnitude substantially over 180°.

FIGS. 10 a,b,c,d,f and g present different variations of ropingarrangements between the traction sheave and the divertingpulley/diverting pulleys, in which the ropes go downwards from the drivemachine towards the counterweight and the elevator car. In the case ofan elevator embodiment according to the invention with machine below,these roping arrangements can be inverted and implemented in acorresponding manner so that the ropes go upwards from the elevatordrive machine towards the counterweight and the elevator car. FIG. 11presents yet another embodiment of the invention, wherein the elevatordrive machine 1106 is fitted together with a diverting pulley 1115 onthe same mounting base 1121 in a ready-made unit 1120, which can befitted as such to form a part of an elevator according to the invention.The unit contains the elevator drive machine 1106, the traction sheave1107 and diverting pulley 1115 ready-fitted on the mounting base 1121,the traction sheave and diverting pulley being ready fitted at a correctoperating angle relative to each other, depending on the ropingarrangement used between the traction sheave 1107 and the divertingpulley 1115. The unit 1120 may comprise more than only one divertingpulley 1115, or it may only comprise the drive machine 1106 fitted onthe mounting base 1121. The unit can be mounted in an elevator accordingto the invention like a drive machine, the mounting arrangement beingdescribed in greater detail in connection with the previous figures. Ifnecessary, the unit can be used together with any of the ropingarrangements described above, such as e.g. embodiments using ESW, DW, SWor XW roping. By fitting the above-described unit as part of an elevatoraccording to the invention, considerable savings can be made ininstallation costs and in the time required for installation.

It is obvious to the person skilled in the art that differentembodiments of the invention are not limited to the examples describedabove, but that they may be varied within the scope of the followingclaims. For instance, the number of times the hoisting ropes are passedbetween the upper part of the elevator shaft and the counterweight orelevator car is not a very decisive question as regards the basicadvantages of the invention, although it is possible to achieve someadditional advantages by using multiple rope passages. In general,embodiments should be so implemented that the ropes go to the elevatorcar at most as many times as to the counterweight. It is also obviousthat the hoisting ropes need not necessarily be passed under the car;instead, they may also be passed over or sideways past the elevator car.In accordance with the examples described above, the skilled person canvary the embodiment of the invention, while the traction sheaves andrope pulleys, instead of being coated metal pulleys, may also beuncoated metal pulleys or uncoated pulleys made of some other materialsuited to the purpose.

It is further obvious to the person skilled in the art that the metallictraction sheaves and rope pulleys used in the invention, which arecoated with a nonmetallic material at least in the area of theirgrooves, may be implemented using a coating material consisting of e.g.rubber, polyurethane or some other material suited to the purpose.

It is also obvious to the person skilled in the art that the elevatorcar, the counterweight and the machine unit may be laid out in thecross-section of the elevator shaft in a manner differing from thelay-out described in the examples. Such a different lay-out might bee.g. one in which the machine and the counterweight are located behindthe car as seen from the shaft door and the ropes are passed under thecar diagonally relative to the bottom of the car. Passing the ropesunder the car in a diagonal or otherwise oblique direction relative tothe form of the bottom provides an advantage when the suspension of thecar on the ropes is to be made symmetrical relative to the center ofmass of the elevator in other types of suspension lay-out as well.

It is further obvious to the person skilled in the art that theequipment required for the supply of power to the motor and theequipment needed for elevator control can be placed elsewhere than inconnection with the machine unit, e.g. in a separate instrument panel.It is also possible to fit pieces of equipment needed for control intoseparate units which can then be disposed in different places in theelevator shaft and/or in other parts of the building. It is likewiseobvious to the skilled person that an elevator applying the inventionmay be equipped differently from the examples described above. It isfurther obvious to the skilled person that the suspension solutionsaccording to the invention can also be implemented using some other typeof flexible hoisting means as hoisting ropes than the means describedhere, to achieve small deflection diameters of the hoisting means, forexample by using flexible rope of one or more strands, flat belt, coggedbelt, trapezoidal belt or some other type of belt applicable to thepurpose, or even using different types of chains.

It is also obvious to the skilled person that, instead of using ropeswith a filler as illustrated in FIG. 5 a and 5 b, the invention may beimplemented using ropes without filler, which are either lubricated orunlubricated. In addition, it is also obvious to the person skilled inthe art that the ropes may be twisted in many different ways. It is alsoobvious to the skilled person that the average of the wire thicknessesmay be understood as referring to a statistical, geometrical orarithmetical mean value. To determine a statistical average, thestandard deviation or Gauss distribution can be used. It is furtherobvious that the wire thicknesses in the rope may vary, e.g. even by afactor of 3 or more.

It is also obvious to the person skilled in the art that the elevator ofthe invention can be implemented using different roping arrangements forincreasing the contact angle α between the traction sheave and thediverting pulley/diverting pulleys than those described as examples. Forexample, it is possible to dispose the diverting pulley/divertingpulleys, the traction sheave and the hoisting ropes in other ways thanin the roping arrangements described in the examples.

1. Elevator, preferably machineroomless elevator, wherein the thicknessof hoisting ropes is below 8 mm and/or the diameter of the tractionsheave is smaller than 320 mm and wherein the overall contact betweenthe traction sheave and a hoisting rope exceed a contact angle of 180°.2. Elevator according to claim 1, wherein a hoisting machine engages aset of hoisting ropes by means of a traction sheave, said set ofhoisting ropes comprising hoisting ropes of substantially circularcross-section, and in which elevator the set of hoisting ropes supportsa counterweight and an elevator car moving on their respective tracks,and that the substantially round hoisting rope has a thickness below 8mm and/or the diameter of the traction sheave is smaller than 320 mm andthat the contact angle between the hoisting rope or hoisting ropes andthe traction sheave is larger than 180°.
 3. Elevator according to claim1, wherein between the traction sheave and the hoisting ropes there is acontinues contact angle of at least 180°.
 4. Elevator according to claim1, wherein the contact angle on the traction sheave consists of 2 ormore parts.
 5. Elevator according to claim 1, wherein the roping of thetraction sheave is implemented using ESW roping.
 6. Elevator accordingto claim 1, wherein the roping of the traction sheave is implementedusing DW roping.
 7. Elevator according to claim 1, wherein the roping ofthe traction sheave is implemented using XW roping.
 8. Elevatoraccording to claim 1, wherein the elevator car and/or the counterweightare suspended with a suspension ratio of 2:1.
 9. Elevator according toclaim 1, wherein the elevator car and/or the counterweight are suspendedwith a suspension ratio of 1:1.
 10. Elevator according to claim 1,wherein the elevator car and/or the counterweight are suspended with asuspension ratio of 3:1.
 11. Elevator according to claim 1, wherein theelevator car and/or the counterweight are suspended with a suspensionratio of 4:1 or even with a higher suspension ratio.
 12. Elevatoraccording to claim 1, wherein the counterweight is suspended n:1 and thecar is suspended m:1 and m is an integer at least 1 and n is an integergreater than m.
 13. Elevator according to claim 1, wherein the averageof the wire thicknesses of the steel wires of the hoisting ropes isabout 0.5 mm, and that the strength of the steel wires is greater than2000 N/mm^(Z).
 14. Elevator according to claim 1, wherein the average ofthe wire thicknesses of the steel wires of the hoisting ropes is greaterthan about 0.1 mm and less than about 0.4 mm.
 15. Elevator according toclaim 1, wherein the average of the wire thicknesses of the steel wiresof the hoisting ropes is greater than about 0.15 mm and less than about0.3 mm.
 16. Elevator according to claim 1, wherein it is alsoimplemented according to at least two of the other preceding claims. 17.Elevator according to claim 1, wherein the strength of the steel wiresof the hoisting ropes is greater than about 2300 N/mm² and less thanabout 2700 N/mm ^(Z).
 18. Elevator according to claim 1, wherein theweight of the hoisting machine of the elevator is at most about ⅕ of theweight of the nominal load of the elevator.
 19. Elevator according toany one of the preceding claims, wherein the outer diameter of thetraction sheave driven by the hoisting machine of the elevator is atmost about 250 mm.
 20. Elevator according to claim 1, wherein the weightof the hoisting machine of the elevator is at most about 100 kg. 21.Elevator according to claim 1, wherein the hoisting machine is ofgearless type.
 22. Elevator according to claim 1, wherein the hoistingmachine is of geared type.
 23. Elevator according to claim 1, whereinthe rope of the overspeed governor is thicker in diameter than thehoisting ropes.
 24. Elevator according to claim 1, wherein the overspeedgovernor rope is of the same thicknesses in diameter as the hoistingropes.
 25. Elevator according to claim 1, wherein the weight of theelevator machine is at most about ⅙ of the nominal load, preferably atmost about ⅛ of the nominal load, very preferably less than about{fraction (1/10)} of the nominal load.
 26. Elevator according to claim1, wherein the total weight of the elevator machine and its supportingelements is at most ⅕ of the nominal load, preferably at most about ⅛ ofthe nominal load.
 27. Elevator according to claim 1, wherein thediameter of the pulleys supporting the car is equal to or less than theheight dimension of a horizontal beam comprised in the structuresupporting the car.
 28. Elevator as defined in claim 1, wherein thepulleys are placed at least partially inside the beam.
 29. Elevator asdefined in claim 1, wherein the track of the elevator car is in anelevator shaft.
 30. Elevator as defined in claim 1, wherein at leastpart of the spaces between strands and/or wires in the hoisting ropes isfilled with rubber, urethane or some other medium of substantiallynon-fluid nature.
 31. Elevator as defined in claim 1, wherein thehoisting ropes have a surface part made of rubber, urethane or someother non-metallic material.
 32. Elevator according to claim 1, whereinthe hoisting ropes are uncoated.
 33. Elevator as defined in claim 1,wherein the traction sheave and/or rope pulleys are/is coated at leastin their/its rope grooves with a non-metallic material.
 34. Elevator asdefined in claim 1, wherein the traction sheave and/or rope pulleysare/is made of a non-metallic material at least in the rim partcomprising the rope grooves.
 35. Elevator as defined in claim 1, whereinthe traction sheave is uncoated.
 36. Elevator according to claim 1,wherein the both the counter weight and the elevator car are suspendedusing a diverting pulley.
 37. Elevator according to claim 1, wherein thehoisting ropes are passed under, over or sideways past the elevator carby means of diverting pulleys mounted on the elevator car.
 38. Elevatoraccording to claim 1, wherein at least the traction sheave and/or therope pulleys form together with the hoisting ropes a material pair thatallows the hoisting rope to bite into the traction sheave and/or intothe rope pulley after the coating on the traction sheave has worn out.39. Elevator according to claim 1, wherein the elevator comprises amounting base on which the hoisting machine with the traction sheave andat least one diverting pulley are mounted, and that the mounting basedetermines the relative positions of and distance between the divertingpulley and the traction sheave.
 40. Elevator according to claim 1,wherein at least the elevator hoisting machine, traction sheave,diverting pulley and mounting base have been fitted as a ready-madeunit.